1. Field of the Invention
This invention relates to an improved thermostatically operated valve construction and method of making the same.
2. Prior Art Statement
It is known to provide a valve construction having a valve seat and a movable valve member for opening and closing the valve seat and being operatively interconnected to a thermal power element carried by the valve construction, the valve member having an annular metallic part for engaging the valve seat to close the same and having an annular flexible part for also engaging the valve seat upstream from the metallic part to augment the closing of the valve seat.
For example, see the following three U.S. Patents:
(1) U.S. Pat. No. 2,873,070--Drapeau PA1 (2) U.S. Pat. No. 3,057,372--Sutton et al PA1 (3) U.S. Pat. No. 3,540,472--Brady et al
It appears that the valve constructions of items (1), (2) and (3) above each has a main valve member for closing against a valve seat together with an annular flexible member being carried by the valve member for engaging the valve seat outboard of the main valve member and upstream therefrom, the annular flexible part not being attached to the main valve member but merely being held against the same by clamping means or being movable relative thereto.